基于单元金复合物的高导电晶体,具有扩展TTF的dithiolate连接体
Wakako Suzuki1, Emiko Fujiwara, Akiko Kobayashi
1Research Centre for Spectrochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|February 6, 2003
概括
新的黄金复合体表现出高的电导率. 这些材料,[Au(tmdt) ((2))) ((0+) 和[Au(tmdt) ((2))) ((0+),由于其金属特性,显示出对先进电子应用的希望.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 导电材料 导电材料 导电材料
背景情况:
- 单元分子导体对于先进的电子设备至关重要.
- 黄金复合物与扩展的四富二烯 (TTF) 滴氧酸连接物提供了新的导电性质的潜力.
研究的目的:
- 为了合成和表征新的单元金复合物与扩展TTF的dithiolate连接体.
- 为了研究这些新的黄金复合物的电导率和磁性.
主要方法:
- 金复合物的合成 [Au(dmdt) ((2)) ] ((0+) 和 [Au(tmdt) ((2)) ] ((0+).
- 结构分析的同步射线辐射粉体衍射.
- 测量压缩粉样的电导率.
- 测量磁敏度以探测电子行为.
主要成果:
- 合成的黄金复合物[Au(dmdt) ((2))) ((0+) 和[Au(tmdt) ((2))) ((0+) 在室温下表现出高电导率,分别为12和15 S cm(-1).
- 复合物1 ([Au(dmdt) ((2))) ((0+)) 呈现出类似保利的敏感性,表明50K以上的金属行为.
- 复合体2 ([Au(tmdt)(2)](0+)) 在保持高导率的同时,显示了大约100K的磁过渡.
结论:
- 该研究成功制备了高导电的单元金复合物.
- 这些复合体表现出明显的电子和磁性特性,具有在分子电子学中的应用潜力.
- 复合体2的磁转换没有导电性损失突出了其独特的导电特性.
相关概念视频
02:42Ionic Crystal Structures
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
02:18Network Covalent Solids
Network covalent solids contain a three-dimensional network of covalently bonded atoms as found in the crystal structures of nonmetals like diamond, graphite, silicon, and some covalent compounds, such as silicon dioxide (sand) and silicon carbide (carborundum, the abrasive on sandpaper). Many minerals have networks of covalent bonds.
To break or to melt a covalent network solid, covalent bonds must be broken. Because covalent bonds are relatively strong, covalent network solids are typically...
To break or to melt a covalent network solid, covalent bonds must be broken. Because covalent bonds are relatively strong, covalent network solids are typically...
02:42Valence Bond Theory
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
02:58Crystal Field Theory - Octahedral Complexes
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
01:26EDTA: Auxiliary Complexing Reagents
EDTA titrations are usually carried out in highly basic conditions, where the fully deprotonated form of EDTA, Y4−, actively complexes with the free metal ions in the solution. Several metal ions precipitate as hydrous oxide (hydroxides, oxides, or oxyhydroxides) under these conditions, lowering the concentration of free metal ions in the solution. For this reason, auxiliary complexing agents or ligands such as ammonia, tartrate, citrate, or triethanolamine are used in EDTA titrations to...